Conventional power semiconductor modules include respective types such as 1-in-1 having one switching element, 2-in-1 having two switching elements, and 6-in-1 having six switching elements, with outside shapes different from one another. Further, the power semiconductor modules have various ratings in current and voltage different from one another as required from customers. Therefore, products have been designed and manufactured separately in response to the ratings in current and voltage.
FIG. 12 illustrates a sectional view of an example of the conventional power semiconductor module. A multilayered substrate 121 is provided on a fin-base 111 of a cooler 110 in a power semiconductor module 101. The multilayered substrate 121 has a multilayered structure in which a circuit plate 121b is fixed to the front face of an insulating plate 121a, and a metal plate 121c to the rear face of the insulating plate 121a. The multilayered substrate 121 is fixed to the fin-base 111 with joining material 122 such as solder. On the circuit plate 121b, a semiconductor chip 123 is joined with conductive joining material 124 such as solder.
A case 125, which is provided to a circumference of the multilayered substrate 121, accommodates the multilayered substrate 121 and the semiconductor chip 123. A cover 125a is disposed on the upper end of the case 125. An external terminal 126, wherein one end is exposed inside the case 125 and the other end is protruding from the upper end of the case 125, is integrally connected to the case 125. Connections between the semiconductor chips 123 and also between the semiconductor chip 123 and the external terminal 126 are achieved electrically through bonding wires 127. An empty space inside the case 125 is sealed, for example, with sealing material 128 composed of insulating resin in order to insulate the multilayered substrate 121, the semiconductor chip 123, and the bonding wires 127 from one another. A metal ring 129 is mounted to a through-hole disposed to the end part of the case 125 as a way to connect the case 125. Then a screw 130 is provided through the metal ring 129, and then the screw 130 is screwed down to connect the fin-base 111. Moreover, the fin-base 111 is adhered to the bottom face of the case 125 through adhesive 131.
The cooler 110 comprises the fin-base 111, a fin 112 connected to the fin-base 111, and a case 113 that accommodates the fin 112 and is hermetically sealed at the peripheral edge of the fin-base 111. A channel is formed inside the case 113. Feeding coolant to the channel allows heat generated from the semiconductor 123 and then conducted to the fin 112 through the multilayered substrate 121 to cool down.
With regard to conventional power semiconductor modules, products are designed and then manufactured separately corresponding to, for example, the number of semiconductor chips and ratings in current and voltage. Then it takes much expense in time and effort to design and then to manufacture them. Furthermore, it is required for the power semiconductor module to slim down in size and thickness for the sake of automotive application and the like.
Relating to miniaturization of the power semiconductor module, it is provided that a device includes a laminate bus bar on which a semiconductor module and a cooler are connected to the both faces (Patent Literature 1). However, with regard to the power semiconductor module described in Patent Literature 1, as bonding wires are employed in the respective semiconductor modules, it takes much expense in time and effort during manufacturing. Further the outside shape including the cooler is not slimmed down sufficiently because the semiconductor module and the cooler are provided on both faces, respectively.